With the rapid development of Long Term Evolution (LTE) systems, there are increasing new techniques in LTE-Advanced systems. Compared to the LTE systems, LTE-Advanced systems have been enhanced in terms of critical technologies by continuous introduction of Carrier Aggregation (CA) technology, Relay technology, Coordinated Multiple Point (CoMP) technology, enhanced multi-antenna technology, uplink multi-antenna technology and the like.
With the introduction of new technologies such as the CA technology, the number of users that can be served by a system is increasing, and thus there may be a problem of insufficient control channel resources. In the existing CA technology, it is specified that downlink carriers of Physical Hybrid ARQ Indicator Channel (PHICH) resources are consistent with downlink carriers of their corresponding authorization information. In this way, in the case of intersected carrier scheduling, there may be a problem of further insufficient control channel resources.
Since PHICH resources are limited in an LTE system, a greatly increasing number of users may cause transmission of HARQ information of uplink data of users to be limited, thus resulting in inability of transmitting HARQ information of the uplink data.
In addition, in the LTE system, transmission of control information is required to be combined with transmission of Cell-specific Reference Signals (CRS) so that demodulation of the control channel is performed. However, no transmission of CRS information in the New Carrier Type (NCT) results in inability of transmitting PHICH resources in the LTE system, thereby leading to a problem regarding transmission of HARQ information of uplink data.